Field of the Invention
The invention relates to a medical device fixation anchor and in particular with an anchor that is suitable for use with a balloon expandable stent.
Discussion of the Related Art
Various medical devices require some form of fixation or anchoring to a targeted site. Common anchoring means include barbs, hooks, sutures, or other features used to attach a device to the surrounding anatomy. Some examples of devices requiring a means to anchor include vena-cava filters, stents, stent grafts, bile/urinary duct stents, intestinal/gastro stents and liners, occluders, electrophysiological leads, various monitors or diagnostic devices, central venous catheters, and other devices as commonly know in the art. Many of these devices incorporate a balloon expandable component that is expanded to bear against the surrounding anatomy, thus providing an anchoring means. The degree of positional anchoring of the medical device is normally dependent upon the degree of “over-expansion” of the balloon expandable component. When over-expanded, the expandable portion is aggressively forced against the surrounding anatomy, affecting a frictional or “interference-fit” means of anchoring. If the degree of over-expansion is excessive, the surrounding anatomy can be damaged. Conversely, if the degree of over-expansion is minimal, the device may dislodge due to poor anchoring.
An improved means of anchoring a balloon expandable component incorporates expandable anchors or barbs. These expandable anchors eliminate the need for aggressive over-expansion and provide a degree of anchoring if the over-expansion is minimal. An improved, balloon expandable anchor can also improve the retention of the expandable component to the balloon. The improved balloon expandable anchors can be contained within the profile of the expandable device, so they do not interfere with the delivery of the device.